Polypropylene material composition, polypropylene material and application thereof

Abstract

The present invention relates to the field of polypropylene, and discloses a polypropylene material composition, a polypropylene material and its application. The polypropylene material composition of the present invention contains polypropylene and an ethylene-alpha-olefin copolymer, wherein the polypropylene has a melt index of 1-10 g / 10 min at a temperature of 230 ° C and a load of 2.16 kg; the ethylene-alpha-olefin copolymer has a melt index of 0.1-20 g / 10 min at a temperature of 190 ° C and a load of 2.16 kg, and the structural unit of the alpha-olefin has a molecular chain dispersion index RMD of 102% or more. According to the polypropylene material composition of the present invention, the product prepared therefrom has better transparency while maintaining impact resistance.

Description

Technical Field

[0001] The present invention relates to the field of polypropylene, and in particular to a polypropylene material composition, a polypropylene material and applications thereof. Background Art

[0002] Polypropylene is commonly used in food packaging containers, pharmaceutical packaging blow molding, extrusion or thermoforming containers, etc., because it has excellent mechanical properties and meets requirements such as environmental protection and safety and sanitation. Along with the improvement day by day of people's living standard, this field application still has high transparency and impact resistance to polypropylene materials at low temperatures and has proposed higher challenge and requirement. Homopolymer based on polypropylene or random copolymer based on polypropylene (RCP) can provide desired hardness for many applications, but may have relatively bad impact properties due to polypropylene's high Tg (glass transition temperature). In order to overcome this defect, a combination scheme of using homopolymer based on polypropylene or random copolymer based on polypropylene (RCP) through elastomer impact modification has been proposed. However, compared with described homopolymer and random copolymer, this impact-modified copolymer may have relatively bad modulus and transparency. Therefore, need can provide toughness and hardness and also can provide the polyolefin composition of transparency. Summary of the Invention

[0003] The purpose of the present invention is to overcome the above-mentioned defects of polypropylene packaging products and provide a polypropylene material composition, a polypropylene material and its application. The polypropylene material composition can be used for blow molding, extrusion or thermoforming products for food, medicine or cosmetic packaging. Compared with traditional modified polypropylene packaging products, this packaging product can maintain impact resistance while having better transparency with a lower amount of comonomer.

[0004] To achieve the above-mentioned object, the present invention provides, in a first aspect, a polypropylene material composition, wherein the composition contains polypropylene and an ethylene-α-olefin copolymer, wherein the polypropylene has a melt index of 1-10 g / 10 min at a temperature of 230° C. and a load of 2.16 kg; the ethylene-α-olefin copolymer has a melt index of 0.1-20 g / 10 min at a temperature of 190° C. and a load of 2.16 kg, and the molecular chain dispersion index (RMD) of the structural units of the α-olefin is greater than 102%.

[0005] Preferably, based on the total weight of the polypropylene and the ethylene-α-olefin copolymer, the content of the polypropylene is 60-90 wt%, and the content of the ethylene-α-olefin copolymer is 10-40 wt%.

[0006] Preferably, the polypropylene has a melt index of 1-4 g / 10 min at a temperature of 230° C. and a load of 2.16 kg.

[0007] Preferably, the ethylene-α-olefin copolymer has a melt index of 1-10 g / 10 min at a temperature of 190° C. and a load of 2.16 kg.

[0008] Preferably, the molecular chain dispersion index RMD of the structural units of the α-olefin is above 103%, preferably 103.5-108%.

[0009] Preferably, the ethylene-α-olefin copolymer contains 5-30 mol% of structural units derived from α-olefin, more preferably 10-25 mol%, further preferably 12-20 mol%.

[0010] Preferably, the molecular weight distribution of the ethylene-α-olefin copolymer is 1.5-3, preferably 1.8-2.5, more preferably 2-2.3.

[0011] Preferably, the α-olefin is an olefin having 5 to 8 carbon atoms, preferably one or more of 1-pentene, 1-hexene, 1-octene and 4-methyl-1-pentene, more preferably 1-octene.

[0012] Preferably, the polypropylene material composition further contains 0.01-3 wt% of an antioxidant, preferably 0.1-1.5 wt% of an antioxidant.

[0013] Preferably, the antioxidant is one or more of a hindered phenol antioxidant, a phosphite antioxidant, and a pentaerythritol ester antioxidant, more preferably one or more of a phosphite antioxidant and a hindered phenol antioxidant.

[0014] Preferably, the polypropylene material composition further contains at least one of an acid absorber, a light stabilizer and a heat stabilizer.

[0015] According to a second aspect of the present invention, there is provided a polypropylene material, which is obtained by melt-blending and molding the polypropylene material composition described in the first aspect of the present invention.

[0016] Preferably, the melt blending temperature is 150-270°C, preferably 170-240°C.

[0017] According to a third aspect of the present invention, there is provided a shaped article, which is formed by blow molding the polypropylene material according to the second aspect of the present invention.

[0018] According to a fourth aspect of the present invention, there is provided the use of the polypropylene material composition described in the first aspect of the present invention and the polypropylene material described in the second method of the present invention in preparing blow-molded, extruded or thermoformed products for food, medicine or cosmetic packaging.

[0019] Through the above technical solution, the present invention can provide a polypropylene material composition, a polypropylene material and its application. The polypropylene material composition can be used for blow molding, extrusion or thermoforming products for food, medicine or cosmetic packaging. Compared with traditional modified polypropylene packaging products, this packaging product can maintain impact resistance while having better transparency with a smaller amount of comonomer. DETAILED DESCRIPTION

[0020] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0021] According to a first aspect of the present invention, a polypropylene material composition is provided, wherein the composition contains polypropylene and an ethylene-α-olefin copolymer, wherein the polypropylene has a melt index of 1-10 g / 10 min at a temperature of 230° C. and a load of 2.16 kg; the ethylene-α-olefin copolymer has a melt index of 0.1-20 g / 10 min at a temperature of 190° C. and a load of 2.16 kg, and the molecular chain dispersion index (RMD) of the structural units of the α-olefin is greater than 102%.

[0022] According to the present invention, preferably, based on the total weight of the polypropylene and the ethylene-α-olefin copolymer, the content of the polypropylene is 60-90 wt%, and the content of the ethylene-α-olefin copolymer is 10-40 wt%.

[0023] Specific examples of the polypropylene content include 60% by weight, 61% by weight, 62% by weight, 63% by weight, 64% by weight, 65% by weight, 66% by weight, 67% by weight, 68% by weight, 69% by weight, 70% by weight, 71% by weight, 72% by weight, 73% by weight, 74% by weight, 75% by weight, 76% by weight, 77% by weight, 78% by weight, 79% by weight, 80% by weight, 81% by weight, 82% by weight, 83% by weight, 84% by weight, 85% by weight, 86% by weight, 87% by weight, 88% by weight, 89% by weight, and 90% by weight.

[0024] Specific examples of the content of the ethylene-α-olefin copolymer include 10% by weight, 11% by weight, 12% by weight, 13% by weight, 14% by weight, 15% by weight, 16% by weight, 11% by weight, 18% by weight, 19% by weight, 20% by weight, 21% by weight, 22% by weight, 23% by weight, 24% by weight, 25% by weight, 26% by weight, 27% by weight, 28% by weight, 29% by weight, 30% by weight, 31% by weight, 32% by weight, 33% by weight, 34% by weight, 35% by weight, 36% by weight, 37% by weight, 38% by weight, 39% by weight, and 40% by weight.

[0025] In the ethylene-α-olefin copolymers provided by the present invention, the comonomer structural units are dispersed in a "super-random" manner throughout the molecular chain. This means that the ethylene structural units are very evenly and effectively dispersed among the copolymerized α-olefin structural units. Therefore, a specific melting point and density can be achieved with a relatively low amount of comonomer. This effectively reduces the raw material costs of the polymer.

[0026] As used herein, the term "super random" dispersion refers to the presence of isolated comonomer units in the ethylene-α-olefin copolymers of the present invention, rather than in a series or block structure. In the ethylene-α-olefin copolymers of the present invention, the comonomer is found to be dispersed throughout the polymer chain to a greater degree than would be expected from an ideal random distribution.

[0027] According to the present invention, preferably, the polypropylene has a melt index of 1-4 g / 10 min at a temperature of 230° C. and a load of 2.16 kg.

[0028] The melt index of the polypropylene at a temperature of 230° C. and a load of 2.16 kg can be, for example, 1.0 g / 10 min, 2.0 g / 10 min, 3.0 g / 10 min, 4.0 g / 10 min, 5.0 g / 10 min, 6.0 g / 10 min, 7.0 g / 10 min, 8.0 g / 10 min, 9.0 g / 10 min, or 10.0 g / 10 min.

[0029] According to the present invention, preferably, the density of the ethylene-α-olefin copolymer is 0.856-0.896 g / cm 3 More preferably, the density of the ethylene-α-olefin copolymer is 0.860-0.880 g / cm 3 .

[0030] According to the present invention, preferably, the ethylene-α-olefin copolymer has a melt index of 1-10 g / 10 min at a temperature of 190° C. and a load of 2.16 kg.

[0031] The melt index MFRC of the ethylene-α-olefin copolymer at a temperature of 190° C. and a load of 2.16 kg can be, for example, 0.1 g / 10 min, 0.2 g / 10 min, 0.3 g / 10 min, 0.4 g / 10 min, 0.5 g / 10 min, 0.6 g / 10 min, 0.7 g / 10 min, 0.8 g / 10 min, 0.9 g / 10 min, 1.0 g / 10 min, 2.0 g / 10 min, 3.0 g / 10 min, and 4.0 g / 10 min. ,5.0g / 10min, 6.0g / 10min, 7.0g / 10min, 8.0g / 10min, 9.0g / 10min, 10.0g / 10min, 11.0g / 10min, 12.0g / 10min, 13 .0g / 10min, 14.0g / 10min, 15.0g / 10min, 16.0g / 10min, 17.0g / 10min, 18.0g / 10min, 19.0g / 10min, 20.0g / 10min, etc.

[0032] According to the present invention, the ethylene-α-olefin copolymer preferably contains 5-30 mol% of structural units derived from α-olefins, more preferably 10-25 mol%, and further preferably 12-20 mol%. In addition, the content of structural units derived from ethylene can be, for example, 70-95 mol%, preferably 75-90 mol%, and more preferably 80-88 mol%.

[0033] Specifically, the content of the structural units derived from ethylene in the ethylene-α-olefin copolymer can be, for example, 70 mol%, 71 mol%, 72 mol%, 73 mol%, 74 mol%, 75 mol%, 76 mol%, 77 mol%, 78 mol%, 79 mol%, 80 mol%, 81 mol%, 82 mol%, 83 mol%, 84 mol%, 85 mol%, 86 mol%, 87 mol%, 88 mol%, 89 mol%, 90 mol%, 91 mol%, 92 mol%, 93 mol%, 94 mol%, 95 mol%, etc.

[0034] Specifically, the content of the structural units derived from α-olefin in the ethylene-α-olefin copolymer can be, for example, 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol%, 16 mol%, 11 mol%, 18 mol%, 19 mol%, 20 mol%, 21 mol%, 22 mol%, 23 mol%, 24 mol%, 25 mol%, 26 mol%, 27 mol%, 28 mol%, 29 mol%, 30 mol%, etc.

[0035] According to the present invention, preferably, the dispersion index RMD of the structural units of the α-olefin in the molecular chain is above 103%; more preferably, the dispersion index RMD of the structural units of the α-olefin in the molecular chain is 103.5-108%; further preferably, the dispersion index RMD of the structural units of the α-olefin in the molecular chain is 104-108%; further preferably, the dispersion index RMD of the structural units of the α-olefin in the molecular chain is 105-108%.

[0036] Specifically, the molecular chain dispersion index RMD of the structural unit of the α-olefin can be, for example, 102, 102.1, 102.2, 102.3, 102.4, 102.5, 102.6, 102.7, 102.8, 102.9, 103, 103.1, 103.2, 103.3, 103.4, 103.5, 103.6, 103.7, 103.8, 103.9, 104, 104.1, 104.2, 104.3, 104.4, 104.5, 104.6, 104. 7, 104.8, 104.9, 105, 105.1, 105.2, 105.3, 105.4, 105.5, 105.6, 105.7, 105.8, 105.9, 106, 106.1, 106.2, 106.3, 106.4, 106.5, 106.6, 106.7, 106.8, 106.9, 107, 107.1, 107.2, 107.3, 107.4, 107.5, 107.6, 107.7, 107.8, 107.9, 108, etc.

[0037] In the present invention, the molecular chain dispersion index RMD of the structural units of the α-olefin is defined by the following formula and is measured as follows:

[0038]

[0039] where AMD represents the absolute comonomer dispersion and BMD represents the completely random comonomer dispersion or Bernoulli dispersion.

[0040] The absolute monomer dispersion AMD is determined as follows. The absolute monomer dispersion is defined as the ratio of the number of comonomer clusters (N) in the average molecule divided by the number of monomer units in the average chain (X). If n1 represents the number of isolated comonomer units and n2 represents adjacent clusters of comonomer units, then the number of adjacent comonomer units in the copolymer is n. x The clusters, X and N are defined as follows:

[0041]

[0042]

[0043] The absolute comonomer dispersion AMD is thus defined as:

[0044]

[0045] Thus, if only isolated comonomer units were present in the polymer molecule, AMD would be 100. Conversely, if all the comonomer units were lumped together, AMD would be 0.

[0046] The ideal random or Bernoulli distributed BMD is determined by the following formula:

[0047]

[0048] Where MC is the concentration of the comonomer in the polymer (in mole percent). Thus, if a polymer consists of 95% ethylene and 5% 1-octene, the BMD is 95.

[0049] The method for calculating the absolute comonomer dispersity (AMD) by nuclear magnetic resonance (NMR) is described as follows:

[0050] When performing NMR spectroscopy on polymers, the NMR peaks can be determined and characterized by their positions relative to tetramethylsilane (ppm). Due to the high operating temperatures, the actual "calibration" is performed relative to hexamethylsiloxane. With E representing the ethylene unit and X the copolymer unit, current calculation methods tend to use a triad distribution to determine the absolute dispersity of the comonomer. Therefore, the carbon atoms attached to the branches can only be one of three types: EXE, EXX, and XXX.

[0051] Since each cluster of two or more X units will contribute two EXX units, the following relationship holds:

[0052] EXE=n1

[0053] EXX=2(n 2+ n 3+ ...n i+...)

[0054] That is:

[0055]

[0056] Likewise, since the triple XXX is found once in XXX, twice in XXXX, three times in XXXXX, and so on:

[0057] XXX=n3+2n4+3n5+…(n-2)n i +…

[0058] Combining the above three formulas, we find that:

[0059] EXE+EXX+XXX=n 1+ 2n2+3n3+…+in i +…=X

[0060] Therefore, the absolute monomer dispersity determined by NMR is:

[0061]

[0062] EXE, EXX and XXX are determined based on the NMR peak height or peak area. In the embodiments of the present invention, X is O, representing 1-octene copolymer units.

[0063] The relative monomer dispersity RMD can be determined according to the above formula. In the following description, the measured relative and absolute monomer dispersities of the comonomers are calculated according to the above formula.

[0064] According to the present invention, the molecular weight distribution Mw / Mn of the ethylene-α-olefin copolymer may be 1.5-3, preferably 1.8-2.5, and more preferably 2-2.3.

[0065] Specifically, the molecular weight distribution Mw / Mn of the ethylene-α-olefin copolymer can be, for example, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3.0.

[0066] In the present invention, the α-olefin is an olefin having 5 to 10 carbon atoms; preferably, the α-olefin is an olefin having 5 to 8 carbon atoms; more preferably, the α-olefin is an olefin having 6 to 8 carbon atoms.

[0067] Examples of the α-olefin include one or more of 1-pentene, 1-hexene, 1-octene, and 4-methyl-1-pentene. Preferably, the α-olefin is 1-octene.

[0068] In another preferred embodiment of the present invention, the ethylene-α-olefin copolymer is an ethylene / α-octene copolymer. Since the ethylene / 1-octene copolymer of the present invention has a high comonomer dispersion index, it can further have better transparency while maintaining impact properties.

[0069] According to the present invention, the ethylene-α-olefin copolymer can be prepared according to the following method, which comprises: copolymerizing ethylene and α-olefin under olefin solution copolymerization conditions in the presence of a catalyst, a co-catalyst and a phenol to obtain the ethylene-α-olefin copolymer;

[0070] The catalyst contains diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride and / or diphenylmethylene (cyclopentadienyl) (2,7-di-tert-butyl-fluorenyl) zirconium dichloride, the co-catalyst is an organoaluminum compound, and the phenol is 2,4-dihalo-1-naphthol.

[0071] The amounts of ethylene and α-olefin used are such that the molar ratio of the structural units derived from ethylene to the structural units derived from α-olefin in the ethylene-α-olefin copolymer is (70-95):(5-30), and the α-olefin is an olefin having 5-10 carbon atoms.

[0072] According to the preparation method of the present invention, preferably, the amount of ethylene and α-olefin used is such that the molar ratio of the structural units derived from ethylene to the structural units derived from α-olefin in the ethylene-α-olefin copolymer is (75-90):(10-25); more preferably, the amount of ethylene and α-olefin used is such that the molar ratio of the structural units derived from ethylene to the structural units derived from α-olefin in the ethylene-α-olefin copolymer is (80-88):(12-20).

[0073] According to the preparation method of the present invention, the amount of the catalyst can be selected according to the amount of ethylene used. Preferably, the amount of the catalyst used in terms of active metal is 0.01-10×10 -6 More preferably, the amount of the catalyst calculated as active metal relative to 1 mol of the ethylene is 0.1-5×10 -6 mol.

[0074] According to the preparation method of the present invention, the organic aluminum compound may be aluminoxane and / or hydrocarbyl aluminum.

[0075] In one embodiment, the organoaluminum compound is aluminoxane, preferably methylaluminoxane (MAO).

[0076] In another embodiment, the organoaluminum compound is a hydrocarbyl aluminum compound represented by Formula 1,

[0077]

[0078] In Formula 1, R1, R2 and R3 are the same or different and are each independently selected from an alkyl group (including a cycloalkyl group), an alkoxy group, an aryl group, an alkaryl group, an aralkyl group and hydrogen, and R1, R2 and R3 are not hydrogen atoms at the same time;

[0079] Specific examples of the alkylaluminum compound may include, but are not limited to, diethylaluminum hydride, di-n-propylaluminum hydride, di-n-butylaluminum hydride, diisobutylaluminum hydride, diphenylaluminum hydride, di-p-tolylaluminum hydride, dibenzylaluminum hydride, phenylethylaluminum hydride, phenyl-n-propylaluminum hydride, p-tolylethylaluminum hydride, p-tolyl-n-propylaluminum hydride, p-tolylisopropylaluminum hydride, benzylethylaluminum hydride, benzyl-n-propylaluminum hydride, benzylisopropylaluminum hydride, ethylaluminum hydride, butylaluminum hydride Aluminum hydride, butylaluminum hydride, isobutylaluminum hydride, octylaluminum hydride, pentylaluminum hydride, diethylaluminum ethoxide, dipropylaluminum ethoxide, trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tripentylaluminum, trihexylaluminum, tricyclohexylaluminum, trioctylaluminum, triphenylaluminum, tri-p-tolylaluminum, tribenzylaluminum, ethyldiphenylaluminum, ethyldi-p-tolylaluminum, ethyldibenzylaluminum, diethylphenylaluminum, diethyl-p-tolylaluminum, and diethylbenzylaluminum.

[0080] In a preferred embodiment, in Formula 1, R1, R2 and R3 are methyl, ethyl, n-propyl, isopropyl, n-butyl or isobutyl. More preferably, in Formula 1, R1, R2 and R3 are all isobutyl.

[0081] According to the preparation method of the present invention, the organoaluminum compound is preferably methylaluminoxane.

[0082] According to the preparation method of the present invention, preferably, the molar ratio of the organoaluminum compound calculated as aluminum to the catalyst calculated as active metal is 50-5000:1, more preferably 200-3000:1, and even more preferably 500-2000:1.

[0083] According to the preparation method of the present invention, the molar ratio of 2,4-dihalo-1-naphthol to the catalyst calculated as active metal is 1-500:1, more preferably 5-300:1, further preferably 10-200:1, further preferably 50-150:1.

[0084] Examples of the 2,4-dihalogeno-1-naphthol include 2,4-dichloro-1-naphthol and / or 2,4-dibromo-1-naphthol, and 2,4-dichloro-1-naphthol is preferred.

[0085] According to the preparation method of the present invention, the α-olefin is an α-olefin with 5-10 carbon atoms; preferably, the α-olefin is an olefin with 5-8 carbon atoms; more preferably, the α-olefin is an olefin with 6-8 carbon atoms.

[0086] Examples of the α-olefin include one or more of 1-pentene, 1-hexene, 1-octene, and 4-methyl-1-pentene. Preferably, the α-olefin is 1-octene.

[0087] According to the preparation method of the present invention, the olefin solution copolymerization conditions may include: a copolymerization temperature of -40 to 200°C, preferably 25 to 120°C; and an ethylene partial pressure of 0.05 to 5 MPa, preferably 0.1 to 2 MPa during polymerization. The polymerization process of the present invention may be carried out in a batch or continuous manner.

[0088] According to the preparation method of the present invention, the polymerization process of the present invention is a solution polymerization process. It should be understood by those skilled in the art that the solvent used therein should be liquid under the polymerization reaction conditions, not react with the catalyst system, and not participate in the polymerization reaction, nor react with the polymer obtained by the reaction, that is, the solvent is inert. Such solvents are obvious to those skilled in the art of coordination polymerization and can be easily selected. Nevertheless, for the present invention, non-polar hydrocarbon solvents can be used. Non-limiting examples of such non-polar hydrocarbon solvents are aromatic hydrocarbons such as benzene, toluene, ethylbenzene, xylene, one or more saturated aliphatic hydrocarbons or alicyclic hydrocarbons such as butane, pentane, hexane, heptane, octane, cyclohexane, or any combination of two or more of the foregoing solvents. Hexane, octane or heptane are preferably used, and hexane is more preferably used as the solvent in the polymerization process of the present invention. For the polymerization process of the present invention, the amount of non-polar hydrocarbon solvent used is conventional and is determined by the polymer dispersibility and the heat dissipation of the system. For example, the amount of solvent used can be controlled so that the monomer concentration is within the range of 5-30wt%, preferably 8-10wt%.

[0089] The multipolymer that obtains in polymerization process of the present invention has very high average molecular weight usually, and those skilled in the art can adopt well-known method to regulate molecular weight.Especially can adopt molecular chain transfer agent such as diethyl zinc and hydrogen as molecular weight regulator to control the molecular weight of multipolymer, preferably adopt hydrogen to realize.Very small amount of hydrogen just can regulate the molecular weight of multipolymer over a large range, and based on the cumulative volume of monomer mixed gas, the addition of hydrogen is 0.01-10 volume %, more preferably 0.02-5 volume %.

[0090] In preparation method of the present invention, can use terminator to stop polyreaction after polyreaction is finished.The terminator that is used for this step is conventional for those skilled in the art.Usually operable terminator comprises deionized water, alcohol, acid etc.Here, the terminator that preferably uses is acidified ethanol or acidified methanol.

[0091] According to the present invention, preferably, the polypropylene material composition further contains 0.01-3 wt% of an antioxidant, preferably 0.1-1.5 wt% of an antioxidant.

[0092] The antioxidant may be any of various agents commonly used for antioxidants in the art, for example, hindered phenol antioxidants and / or phosphite antioxidants.

[0093] Examples of the hindered phenol antioxidant include pentaerythritol tetrakis[methyl-β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], n-octadecylβ-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, and 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione; and examples of the phosphite antioxidant include tris[2,4-di-tert-butylphenyl]phosphite, bis(2,4-di-tert-butylphenol)pentaerythritol diphosphite, and distearyl pentaerythritol diphosphite.

[0094] The polypropylene composition may further contain additives as needed for practical applications. For example, the additives may be selected from at least one of an acid absorber, a light stabilizer, and a heat stabilizer. Furthermore, the amounts of these additives may be conventional in the art and are not described in detail herein.

[0095] According to a second aspect of the present invention, there is provided a polypropylene material, which is obtained by melt-blending and molding the polypropylene material composition described in the first aspect of the present invention.

[0096] In order to help the uniform dispersion of each component in the polypropylene composition, preferably before the melt blending, the polypropylene composition is premixed. In addition, the main improvement of the polypropylene material is that a new polypropylene composition has been adopted as raw material, and the mode and condition of the premixing, melt blending and molding can be the conventional selection of this area. For example, the premixing can be carried out in mechanical mixing equipment such as existing various high-speed stirrers, kneaders, etc. usually. And melt blending and molding can be carried out in the equipment of existing various melting and molding functions in one, for example, can be carried out in equipment such as open mill, internal mixer, single screw extruder, twin screw extruder, Bufair kneader, torque rheometer, etc. In addition, the molding can be extrusion molding. In the process of the molding, the polypropylene material can be squeezed into shapes such as sheet, column, granular according to actual needs.

[0097] According to one embodiment, the polypropylene material is obtained by premixing the components of the polypropylene composition in a high-speed blender, adding the uniformly mixed material to a twin-screw extruder for melt blending, extrusion pelletization, and drying. The melt blending temperature may be 150-270°C, preferably 170-240°C.

[0098] According to a third aspect of the present invention, there is provided a shaped article, which is formed by blow molding the polypropylene material according to the second aspect of the present invention.

[0099] There are no particular conditions for the blow molding, and the blow molding can be carried out under conventional conditions using equipment commonly used in the art.

[0100] According to a fourth aspect of the present invention, there is provided the use of the polypropylene material composition described in the first aspect of the present invention and the polypropylene material described in the second method of the present invention in preparing blow-molded, extruded or thermoformed products for food, medicine or cosmetic packaging.

[0101] The polypropylene material of the present invention can be used for blow molding, extrusion or thermoforming products for food, medicine or cosmetic packaging. Compared with traditional modified polypropylene packaging products, such packaging products have better transparency while maintaining impact resistance.

[0102] The present invention will be described in detail below through examples, but the present invention is not limited to the following embodiments.

[0103] In the following experiments, the test method is as follows.

[0104] (1) Weight average molecular weight and molecular weight distribution test

[0105] The molecular weight and molecular weight distribution of the samples were determined using a PL-GPC 220 GPC from Polymer Laboratories (UK). The chromatographic columns consisted of three Plgel 10μm MIXED-B columns connected in series. The solvent and mobile phase were both 1,2,4-trichlorobenzene (containing 0.025% of the antioxidant 2,6-dibutyl-p-cresol). The column temperature was 150°C, the flow rate was 1.0 ml / min, and the sample concentration was 1 mg / ml. The column was equipped with an IR5 infrared concentration detector, and universal calibration was performed using narrow-distribution polystyrene standards.

[0106] (2) Determination of melt index

[0107] The melt index is measured on a Dynisco LMI melt indexer at a test temperature of 190°C or 230°C and a pressure of 2.16 kg.

[0108] (3) Comonomer content and dispersion test

[0109] The comonomer content of the samples was determined using a Bruker AVANCE III 400 MHz NMR spectrometer. The solvent was deuterated o-dichlorobenzene, and a 10 mm PASEX 13C-1H / D Z-GRD probe was used. A 10% mass concentration of the sample was uniformly dissolved at 130°C. The measurement temperature was 125°C, the rotation speed was 20 Hz, the pulse was 90°, the spectral width was 120 ppm, the sampling time was 5 seconds, the delay time was 10 seconds, and the scans were 6000. The tool monomer content was calculated based on the 13C-NMR spectra using methods described in the literature (e.g., Macromolecules 2000, 33, 8931-8944; Macromolecules 2001, 34, 5770-5777).

[0110] The specific test method for the comonomer dispersion AMD is described in the above description.

[0111] Preparation Example 1

[0112] A 250 ml polymerization apparatus, which had been thoroughly dried, was evacuated and flushed with nitrogen three times. The apparatus was then evacuated again and, controlled by a solenoid valve, filled with ethylene at 1 standard atmosphere. At room temperature, 25 ml of the reaction solvent (toluene), 1 ml of a 2,4-dichloro-1-naphthol solution (containing 0.5 mmol of 2,4-dichloro-1-naphthol), and 0.8 ml of 1-octene were added. Then, 3 ml of a methylaluminoxane (MAO) solution (containing 5.0 mmol of methylaluminoxane) were added. The temperature was raised to 50°C, and 1 ml of a toluene solution containing 5.0 micromolar diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride was added. The timer was started. After 20 minutes, the ethylene was turned off, and acidified ethanol was added to the reaction mixture. The mixture was stirred for at least 6 hours. The resulting polymer was filtered and vacuum dried for 24 hours. The polymer was weighed to yield 1.47 g. The test results are shown in Table 1.

[0113] Preparation Example 2

[0114] A 250 ml polymerization apparatus, which had been thoroughly dried, was evacuated and flushed with nitrogen three times. The apparatus was then evacuated again and, controlled by a solenoid valve, filled with ethylene at 1 standard atmosphere. At room temperature, 25 ml of the reaction solvent (toluene), 1 ml of a 2,4-dichloro-1-naphthol solution (containing 0.5 mmol of 2,4-dichloro-1-naphthol), and 0.8 ml of 1-octene were added. Then, 3 ml of a methylaluminoxane (MAO) solution (containing 5.0 mmol of methylaluminoxane) were added. The temperature was raised to 70 degrees Celsius, and 1 ml of a toluene solution containing 5.0 micromolar diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride was added. The timer was started. After 20 minutes, the ethylene was turned off, and acidified ethanol was added to the reaction mixture. The mixture was stirred for at least 6 hours. The resulting polymer was filtered and vacuum dried for 24 hours. The polymer was weighed to yield 1.58 g. The test results are shown in Table 1.

[0115] Preparation Example 3

[0116] A 250 ml polymerization apparatus, which had been thoroughly dried, was evacuated and flushed with nitrogen three times. The apparatus was then evacuated again and, controlled by a solenoid valve, filled with ethylene at 1 atmosphere. At room temperature, 25 ml of the reaction solvent (toluene), 1 ml of a 2,4-dichloro-1-naphthol solution (containing 0.5 mmol of 2,4-dichloro-1-naphthol), and 1.0 ml of 1-octene were added. Then, 3 ml of a methylaluminoxane (MAO) solution (containing 5.0 mmol of methylaluminoxane) were added. The temperature was raised to 50°C, and 1 ml of a toluene solution containing 5.0 micromolar diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride was added. The timer was started. After 20 minutes, the ethylene was turned off, and acidified ethanol was added to the reaction mixture. The mixture was stirred for at least 6 hours. The resulting polymer was filtered and vacuum dried for 24 hours. The polymer was weighed to yield 1.51 g. The test results are shown in Table 1.

[0117] Preparation Example 4

[0118] A 250 ml polymerization apparatus, which had been thoroughly dried, was evacuated and flushed with nitrogen three times. The apparatus was then evacuated again and, controlled by a solenoid valve, filled with ethylene at 1 atmosphere. At room temperature, 25 ml of the reaction solvent (toluene), 1 ml of a 2,4-dichloro-1-naphthol solution (containing 0.5 mmol of 2,4-dichloro-1-naphthol), and 1.1 ml of 1-octene were added. Then, 3 ml of a methylaluminoxane (MAO) solution (containing 5.0 mmol of methylaluminoxane) were added. The temperature was raised to 70°C, and 1 ml of a toluene solution containing 5.0 micromolar diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride was added. The timer was started. After 20 minutes, the ethylene was turned off, and acidified ethanol was added to the reaction mixture. The mixture was stirred for at least 6 hours. The resulting polymer was filtered and vacuum dried for 24 hours. The polymer was weighed to yield 1.61 g. The test results are shown in Table 1.

[0119] Preparation Example 5

[0120] A 250 ml polymerization apparatus, which had been thoroughly dried, was evacuated and flushed with nitrogen three times. The apparatus was then evacuated again and, controlled by a solenoid valve, filled with ethylene at 1 standard atmosphere. At room temperature, 25 ml of the reaction solvent (toluene), 1 ml of a 2,4-dichloro-1-naphthol solution (containing 0.5 mmol of 2,4-dichloro-1-naphthol), and 1.3 ml of 1-octene were added. Then, 3 ml of a methylaluminoxane (MAO) solution (containing 5.0 mmol of methylaluminoxane) were added. The temperature was raised to 70 degrees Celsius, and 1 ml of a toluene solution containing 5.0 micromolar diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride was added. The timer was started. After 20 minutes, the ethylene was turned off, and acidified ethanol was added to the reaction mixture. The mixture was stirred for at least 6 hours. The resulting polymer was filtered and vacuum dried for 24 hours. The polymer was weighed to yield 1.65 g. The test results are shown in Table 1.

[0121] Preparation Example 6

[0122] A 250 ml polymerization apparatus, which had been thoroughly dried, was evacuated and flushed with nitrogen three times. The apparatus was then evacuated again and, controlled by a solenoid valve, filled with ethylene at 1 atmosphere. At room temperature, 25 ml of the reaction solvent (toluene), 1 ml of a 2,4-dichloro-1-naphthol solution (containing 0.5 mmol of 2,4-dichloro-1-naphthol), and 1.3 ml of 1-hexene were added. Then, 3 ml of a methylaluminoxane (MAO) solution (containing 5.0 mmol of methylaluminoxane) were added. The temperature was raised to 70°C, and 1 ml of a toluene solution containing 5.0 micromolar diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride was added. The timer was started. After 20 minutes, the ethylene was turned off, and acidified ethanol was added to the reaction mixture. The mixture was stirred for at least 6 hours. The resulting polymer was filtered and vacuum dried for 24 hours. The polymer was weighed to yield 1.65 g. The test results are shown in Table 1.

[0123] In Table 1, the ethylene-α-olefin copolymers obtained in Preparation Examples 1-6 are respectively denoted as A1-A6. In addition, comparative ethylene-α-olefin copolymers D1-D3 are also listed in Table 1. D1-D3: Comparative Examples 1-3: Commercial ethylene / 1-octene copolymer samples, with the brands DOW engage8150, engage8137 and engage8842, respectively.

[0124] Table 1

[0125]

[0126] Examples 1-6 and Comparative Examples 1-3

[0127] PPTO3H (melt index 3.0 g / 10 min (230°C, 2.16 kg), from Yangzi Petrochemical) and ethylene-α-olefin copolymers (A1-A6 and D1-D3) were thoroughly mixed under stirring at 90 rpm for 5 minutes. The resulting mixture was extruded and pelletized using a twin-screw extruder (ZSK 25, from Werner & Pfleiderer). The screw speed was controlled at 10 rpm and the torque was 20 Nm. The temperatures in the twin-screw extruder sections from the feed port to the extrusion port were adjusted to 220°C, 220°C, 220°C, 220°C, 220°C, and 220°C, respectively, to produce polypropylene materials AA1-AA6 and DD1-DD3.

[0128] Comparative Example 4

[0129] PPT03H (melt index 3.0 g / 10 min (230° C., 2.16 kg), Yangzi Petrochemical) was used as comparative material DD4.

[0130] Test Example 1

[0131] The polypropylene materials AA1-AA6 and DD1-DD4 of Examples 1-6 and Comparative Examples 1-4 were subjected to haze tests according to the method of GB / T 2410-2008 using an A-4725 transmission haze analyzer from German BYK Company. The results are shown in Table 2.

[0132] Test Example 2

[0133] The impact strength of the polypropylene materials AA1-AA6 and DD1-DD4 of Examples 1-6 and Comparative Examples 1-4 was tested according to GB / T 13525-1992. The results are shown in Table 2.

[0134] Table 2

[0135] Haze <![CDATA[Impact strength (KJ / m 2 )]]> AA1 14.5 6.3 AA2 14.2 6.5 AA3 12.1 6.9 AA4 11.9 7.2 AA5 11.9 7.4 AA6 11.8 7.3 DD1 14.8 5.9 DD2 14.5 5.9 DD3 14.7 6.1 DD4 25.8 4.4

[0136] A comparison of AA1-AA6 and DD1-DD4 in Table 1 shows that the use of the specific ethylene-α-olefin copolymers of the present invention not only exhibits improved impact resistance but also exhibits superior transparency. In particular, transparency is significantly improved when the molecular chain dispersion index (RMD) of the α-olefin structural units is 105% or greater.

[0137] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A polypropylene material composition, characterized in that: The composition contains polypropylene and ethylene-α-olefin copolymer, wherein the polypropylene has a melt index of 1-10 g / 10 min at a temperature of 230° C. and a load of 2.16 kg; the ethylene-α-olefin copolymer has a melt index of 0.1-20 g / 10 min at a temperature of 190° C. and a load of 2.16 kg, and the molecular chain dispersion index (RMD) of the structural unit of the α-olefin is above 102%. The dispersion index RMD of the structural units of the α-olefin in the molecular chain is defined by the following formula: where AMD represents the absolute comonomer dispersion and BMD represents the completely random comonomer dispersion or Bernoulli dispersion.

2. The composition according to claim 1, wherein Based on the total weight of the polypropylene and the ethylene-α-olefin copolymer, the content of the polypropylene is 60-90 weight %, and the content of the ethylene-α-olefin copolymer is 10-40 weight %.

3. The composition according to claim 1, wherein The polypropylene has a melt index of 1-4 g / 10 min at a temperature of 230° C. and a load of 2.16 kg.

4. The composition according to claim 1, wherein The ethylene-α-olefin copolymer has a melt index of 1-10 g / 10 min at a temperature of 190° C. and a load of 2.16 kg.

5. The composition according to any one of claims 1 to 4, wherein The molecular chain dispersion index RMD of the structural units of the α-olefin is greater than 103%.

6. The composition according to claim 5, wherein The molecular chain dispersion index RMD of the structural units of the α-olefin is 103.5-108%.

7. The composition according to any one of claims 1 to 4, wherein The ethylene-α-olefin copolymer contains 5 to 30 mol% of structural units derived from α-olefin.

8. The composition according to claim 7, wherein The ethylene-α-olefin copolymer contains 10 to 25 mol% of structural units derived from α-olefin.

9. The composition according to claim 8, wherein The ethylene-α-olefin copolymer contains 12 to 20 mol% of a structural unit derived from an α-olefin.

10. The composition according to any one of claims 1 to 4, wherein The molecular weight distribution of the ethylene-α-olefin copolymer is 1.5-3.

11. The composition according to claim 10, wherein The molecular weight distribution of the ethylene-α-olefin copolymer is 1.8-2.

5.

12. The composition according to claim 11, wherein The molecular weight distribution of the ethylene-α-olefin copolymer is 2-2.

3.

13. The composition according to any one of claims 1 to 4, wherein The α-olefin is an olefin having 5 to 8 carbon atoms.

14. The composition according to claim 13, wherein The α-olefin is one or more of 1-pentene, 1-hexene, 1-octene and 4-methyl-1-pentene.

15. The composition according to claim 14, wherein The α-olefin is 1-octene.

16. The composition according to any one of claims 1 to 4, wherein The polypropylene material composition further contains 0.01-3 weight percent of an antioxidant.

17. The composition according to claim 16, wherein The polypropylene material composition contains 0.1-1.5 weight percent of an antioxidant.

18. The composition according to claim 16, wherein The antioxidant is one or more of hindered phenol antioxidants, phosphite antioxidants and pentaerythritol ester antioxidants.

19. The composition according to claim 18, wherein The antioxidant is one or more of a phosphite antioxidant and a hindered phenol antioxidant.

20. The composition according to any one of claims 1 to 4, wherein The polypropylene material composition further contains at least one of an acid absorber, a light stabilizer and a heat stabilizer.

21. A polypropylene material, obtained by melt-blending and molding the polypropylene material composition according to any one of claims 1 to 20.

22. The polypropylene material according to claim 21, wherein The temperature of the melt blending is 150-270°C.

23. The polypropylene material according to claim 22, wherein The temperature of the melt blending is 170-240°C.

24. A shaped article formed by blow molding the polypropylene material according to any one of claims 21 to 23.

25. Use of the polypropylene material composition according to any one of claims 1 to 20 and the polypropylene material according to any one of claims 21 to 23 in the preparation of blow-molded, extruded or thermoformed products for food, medicine or cosmetic packaging.

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